pbinom and dbinom functions

If I have a field instrument system has 4 components and can function of at least two of them are working. Each component independently works with probability of 0.8. This is the correct way to find the probability that the system will function?

p <- 0.8
n = 4
X <- 2:4
Prob <- pbinom(X, n, p)

pbinom(x = 2:4, size = 4, prob = 0.8)